AMP⁺ MaxSpec^® Kit

Many lipids have a free carboxylic acid group that typically requires a weak acid mobile phase to ensure retention by HPLC. Unfortunately, the presence of the acid in the mobile phase also suppresses anion formation and often leads to poor electrospray ionization and poor MS sensitivity. Cayman’s AMP⁺ MaxSpec^® Kit contains a positively charged reagent (AMP⁺) that can be coupled quantitatively to free carboxylic acids through an amide bond linkage. The resulting derivatized product thus contains a positively charged group that shows improved electrospray ionization and consequently improved MS sensitivity. Cayman’s derivatization reagent is stable to MS/MS fragmentation and thus isobaric derivatives undergo compound-specific fragmentation to give unique fragment ions.

Limitations: This kit, when used per the instructions outlined in the booklet, produces derivatized stearic acid and palmitic acid interference peaks. Due to these interferences, this kit should not be used for the detection or identification of these two acids in samples.^1,2

WARNING This product is not for human or veterinary use.

1. Yao, C.-H., Liu, G.-Y., Yang, K., et al. Inaccurate quantitation of palmitate in metabolomics and isotope tracer studies due to plastics. Metabolomics 12, 143 (2016).

2. Cavonius, L.R., and Carlsson, N.-G. Fatty acid contaminations originating from commercially available solid phase-extraction columns. Chem. Sci. Rev. Lett. 4(16), 1206-1209 (2015).

Rajagopal, R., Zhang, S., Wei, X., et al. Retinal de novo lipogenesis coordinates neurotrophic signaling to maintain vision. JCI Insight 3(1), e97076 (2018).